Pole hits back (4)
I believe the answer is:
spar
'pole' is the definition.
(spar is a kind of pole)
'hits back' is the wordplay.
'hits' becomes 'raps' (I've seen this in another clue).
'back' says the letters should be written in reverse.
'raps' reversed gives 'SPAR'.
(Other definitions for spar that I've seen before include "Box; various minerals" , "Practise boxing with a pole?" , "Go a few rounds with the ship's pole" , "Pole-shaped part of the rigging" , "Box - mineral - rod" .)